Figure 1 A concept w, for example red, is represented in some contextual probe c which takes the form of a choice of basis. This low dimensional representation shows a case of some object being classified by a probe as “red” (|1)) or “not red” (|0)), with the probability of that a “red” judgment being given by |a;|?. In a higher number of dimensions the property of redness will be enclosed by a convex region, and the probabilities lie in a range of values specified by the extent of that region. Here, {|0,) = (0, 1)”, |1,) = (1,0)"} define an orthonormal